[clang][dataflow] Remove stray lines from `Environment::join`

[ymandel]

Summary

Removes an assertion and a useless line. The assertion seems left over from
earlier debugging and the line that follows is a stray line.

clang/lib/Analysis/FlowSensitive/DataflowEnvironment.cpp

if (DeclToLoc.size() != JoinedEnv.DeclToLoc.size())
     Effect = LatticeJoinEffect::Changed;
 
   JoinedEnv.ExprToLoc = intersectDenseMaps(ExprToLoc, Other.ExprToLoc);
   if (ExprToLoc.size() != JoinedEnv.ExprToLoc.size())
     Effect = LatticeJoinEffect::Changed;
 
   JoinedEnv.MemberLocToStruct =
       intersectDenseMaps(MemberLocToStruct, Other.MemberLocToStruct);
-  assert(JoinedEnv.MemberLocToStruct.size() <=
-         std::min(MemberLocToStruct.size(), Other.MemberLocToStruct.size()));
-
-  intersectDenseMaps(MemberLocToStruct, Other.MemberLocToStruct);
   if (MemberLocToStruct.size() != JoinedEnv.MemberLocToStruct.size())
     Effect = LatticeJoinEffect::Changed;
 
   // FIXME: set `Effect` as needed.
   // FIXME: update join to detect backedges and simplify the flow condition
   // accordingly.
   JoinedEnv.FlowConditionToken = &DACtx->joinFlowConditions(
       *FlowConditionToken, *Other.FlowConditionToken);